* {
    box-sizing: border-box;
}

h1 {
    margin-bottom: 10px;
}

body {
    font-family: Arial, Helvetica, sans-serif;
}

a {
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

header {
    background-color: #f45a15;
    padding: 15px;
    font-size: 25px;
    color: white;
    border: 0;
}

header img {
    width: 250px;
}

section {
    display: -webkit-flex;
    display: flex;
}

/* Style the navigation menu */
nav {
    -webkit-flex: 1;
    -ms-flex: 1;
    flex: 1;
    background: #eaeaea;
    padding: 40px;
}

.menu-a {
    cursor: pointer;
}

.menu-li {
    padding-bottom: 10px;
}

article {
    -webkit-flex: 3;
    -ms-flex: 3;
    flex: 3;
    background-color: #f1f1f1;
    padding: 30px;
}

#hamburger {
    position: relative;
    left: -25px;
    top: -27px;
    cursor: pointer;
}

footer {
    background-color: #f45a15;
    padding: 10px;
    text-align: center;
    color: white;
}

/* Responsive layout - makes the menu and the content (inside the section) sit on top of each other instead of next to each other */
@media (max-width: 300px) {
    section {
        -webkit-flex-direction: column;
        flex-direction: column;
    }
}

.stack-horizontally-container {
    overflow-y: hidden;
}

.stack-horizontally {
    float: left;
}

#hamburger {
    width: 20px;
    height: 20px;
}

@media (min-width: 100px) AND (max-width: 640px) {
    header img {
        width: 80px;
    }
    
    article, nav {
        margin-left: auto;
        margin-right: auto;
    }
    
    .menu-li {
        padding-bottom: 32px;
    }
    
    #hamburger {
        width: 48px;
        height: 48px;
    } 
}